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/*
*
* Authors:
* Pedro Roque <roque@di.fc.ul.pt>
* Lars Fenneberg <lf@elemental.net>
*
* This software is Copyright 1996,1997 by the above mentioned author(s),
* All Rights Reserved.
*
* The license which is distributed with this software in the file COPYRIGHT
* applies to this software. If your distribution is missing this file, you
* may request it from <reubenhwk@gmail.com>.
*
*/
#include "config.h"
#include "includes.h"
#include "radvd.h"
int recv_rs_ra(int sock, unsigned char *msg, struct sockaddr_in6 *addr, struct in6_pktinfo **pkt_info, int *hoplimit,
unsigned char *chdr)
{
struct iovec iov;
iov.iov_len = MSG_SIZE_RECV;
iov.iov_base = (caddr_t)msg;
struct msghdr mhdr;
memset(&mhdr, 0, sizeof(mhdr));
mhdr.msg_name = (caddr_t)addr;
mhdr.msg_namelen = sizeof(*addr);
mhdr.msg_iov = &iov;
mhdr.msg_iovlen = 1;
mhdr.msg_control = (void *)chdr;
mhdr.msg_controllen = CMSG_SPACE(sizeof(struct in6_pktinfo)) + CMSG_SPACE(sizeof(int));
int len = recvmsg(sock, &mhdr, 0);
if (len < 0) {
if (errno != EINTR)
flog(LOG_ERR, "recvmsg: %s", strerror(errno));
return len;
}
*hoplimit = 255;
for (struct cmsghdr *cmsg = CMSG_FIRSTHDR(&mhdr); cmsg != NULL; cmsg = CMSG_NXTHDR(&mhdr, cmsg)) {
if (cmsg->cmsg_level != IPPROTO_IPV6)
continue;
switch (cmsg->cmsg_type) {
#ifdef IPV6_HOPLIMIT
case IPV6_HOPLIMIT:
if ((cmsg->cmsg_len == CMSG_LEN(sizeof(int))) && (*(int *)CMSG_DATA(cmsg) >= 0) &&
(*(int *)CMSG_DATA(cmsg) < 256)) {
*hoplimit = *(int *)CMSG_DATA(cmsg);
} else {
flog(LOG_ERR, "received a bogus IPV6_HOPLIMIT from the kernel! len=%d, data=%d",
(int)cmsg->cmsg_len, *(int *)CMSG_DATA(cmsg));
return -1;
}
break;
#endif /* IPV6_HOPLIMIT */
case IPV6_PKTINFO:
if ((cmsg->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) &&
((struct in6_pktinfo *)CMSG_DATA(cmsg))->ipi6_ifindex) {
*pkt_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
} else {
flog(LOG_ERR, "received a bogus IPV6_PKTINFO from the kernel! len=%d, index=%d",
(int)cmsg->cmsg_len, ((struct in6_pktinfo *)CMSG_DATA(cmsg))->ipi6_ifindex);
return -1;
}
break;
}
}
char if_namebuf[IF_NAMESIZE] = {""};
char *if_name = 0;
if (pkt_info && *pkt_info) {
if_name = if_indextoname((*pkt_info)->ipi6_ifindex, if_namebuf);
}
if (!if_name) {
if_name = "unknown interface";
}
dlog(LOG_DEBUG, 5, "%s recvmsg len=%d", if_name, len);
return len;
}
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